Limits

Pipeline visibility is all or nothing

Pipeline access is fleet-wide: open Pipelines and you see every pipeline in your instance, or none. There is no per-pipeline or per-team scope, and that includes task logs.

No column masking or row-level security

Data access is granted per warehouse, namespace or table. There is no column masking and no row-level filtering, in the catalog, in Trino or in Superset. To show a group only some columns or rows, write them to a separate table (for example in a pipeline) and grant that table.

No groups in Access control

Feature permissions are given to people directly or through roles. There are no groups, and roles cannot contain other roles.

Lineage is limited to table history

Each Iceberg table keeps its own snapshot history, but there is no lineage view across tables, pipelines and dashboards.

No external SQL clients

Query the lakehouse from notebooks, SQL Lab, dashboards and pipelines. Connecting external BI tools or SQL clients directly is not supported.

Dashboards are a door, not a filter

Everyone who can open Superset sees the same charts, dashboards and datasets; only which queries return rows differs, decided by data grants, so a chart on data you have no grant for errors. See how access works.

The catalog preview is a sample, not a query

The Preview tab shows the first 20 rows of a table’s current snapshot, so it cannot filter, join or aggregate and never shows the whole table. To read for real, use a notebook or SQL Lab. See table details.

Generic tables have no preview or schema

A non-Iceberg table has no snapshots, so it shows no preview and no schema — only its format, location and permissions. See Iceberg tables.

A notebook scan uses session memory

A notebook server has 4 GB of memory and 2 CPUs by default, and a scan loads everything it reads into that memory, so an unbounded scan of a large table exhausts the session. Narrow it — pick columns, filter rows, cap the size — or run it in SQL Lab, where Trino returns only the result. See querying data.

If you need more, ask your platform administrator.

Notebook storage is not backed up

Your home (10 GB by default) and the shared folder persist across restarts but are not backed up, and /tmp is cleared each start. Treat the git remote as source of truth and push often. See notebook storage and working with Git.

SQL Lab queries stop after 300 seconds

A SQL Lab query that runs longer than 300 seconds is cancelled. Narrow it, or move the work into a pipeline.

Sign-ins expire

A sign-in and its query token have a limited lifetime, so a long or idle session ages out and queries stop authenticating. Sign in again — in a notebook, that shows up as an authentication error saying your login could not be refreshed; sign out of Notebooks and back in (the catalog itself does not need re-creating, see your catalog does not go stale). In Superset the token lasts about 15 minutes and is not refreshed in the background, so queries there can fail sooner; sign out and back in.